The invention relates to a precombustion chamber device for the ignition of preferably lean fuel-air mixtures comprising a precombustion chamber, which contains an electrode carrier extending into the precombustion chamber and having at least one ignition electrode attached to it, said electrode having at least one ignition portion, which with an inner wall surface of the precombustion chamber defines a spark gap directed substantially athwart the longitudinal axis of the precombustion chamber, such inner wall surface functioning as a ground electrode.